Materials handling vehicles commonly include braking systems which combine regenerative braking using the vehicle traction motor, which may be referred to as plugging, with mechanical brakes. Since regenerative braking conserves battery charge and is not subject to wear as are mechanical brakes, it is desirable to use the electric motor for as much of the normal service braking requirements as possible. Provided the traction motor has sufficient capacity, substantially all service braking can be done using the traction motor with the mechanical brakes being used only for parking and backup braking which may be required during unusual operating circumstances such as use of the vehicles on excessive grades and/or with inadvertently excessive loads.
In instances where the vehicle's primary form of braking is regenerative braking or its construction is such that a mechanical brake is separated from the wheel-end of the drivetrain, a series of mechanical interconnecting joints are used to transmit tractive and braking forces to the wheels of the vehicle. If critical ones of these interconnecting mechanical components become loose or structurally fail, braking and handling characteristics of the vehicle can be adversely affected.